Cylinder block constructions and methods and apparatus for making same or the like



Jan. 19, 1965 J. a. THOMAS 3,165,983

CYLINDER B K CONSTRUCTIONS ME 5 AND APPARAT FOR MAKING SAME THE LSheets-Sheet 1 Filed Sept. 22, 1961 JNVEVTOR. JESSE 8. THOMAS HISATTORNEYS Jan. 19, 1965 J. B. THOMAS 3,165,983

CYLIN BLOCK CONSTRUCTIONS AND METH AND AP ATUS FOR MAKING SAME OR THE KEFiled Sept. 22, 1961 3 Sheets-Sheet 2 s M m m w m m c m in I w. B c m mmm 2, 2 r m 5 4 g {v ll MW a I N i H fifi M l JP fl C ,M H W 1 o -q 2LO% 0 2 5 a w m uv n, w M k M w C I, u L 'lll "L7, 6 5 ll lb I 4 F JFG w2. i r

Jan. 19, 1965 J. B. THO

' CYLINDER BLOCK CONSTRUCTI MAS ONS AND METHODS'AND APPARATUS FOR MAKINGSAME OR THE LIKE Filed Sept. 22. 1961 3 Sh eets-Shee t 3 INVENTOR. JESSEB. THOMAS H S ATTORNEYS United States Patent CYLINDER BLQCKCONSTRUCTIGNS AND METH- ODS ANI) AFPARATUS FOR MAKING AME GK THE LIKEEesse B. Thomas, Iiemico (Jonnty, Va, assignor to Reynolds MetalsCompany, Richmond, Vin, a corporation of Delaware Filed Sept. 22, 1961,Ser; No. 1%,111

15 Claims. (Cl. 92-469) This invention relates to improved cylinderblock constructions or the like and to improved methods and apparatusfor making such cylinder block constructions or the like.

It is well known in the art that cylinder blocks for internal combustionengines and the like have been formed by casting or otherwisesurrounding cylinder block material, such as aluminum-containingmetallic material and the like, about one or more cylinder-definingmembers formed of steel or the like whereby the cylinder-definingmembers are formed of wear resistant materials and the remainder of thecylinder block construction is formed of good heat conducting andlight-weight materials. The cylinder block material is usually bonded tothe cylinderdefining members or mechanically locked thereto.

However, it has been found that such prior known bonding or mechanicallylocking means are inadequate and the cylinder-defining members tend toreadily break loose from the cylinder block material during continueduse of the cylinder block constructions. Such cylinder block failurc isparticularly aggravated when he cylinder-defining members are formed ofone aluminum alloy and the cylinder block material is formed of anotheraluminum loy.

According to the teachings of this invention, however,

an improved cylinder block construction and method and apparatus formaking the same areprovided wherein the cylinder-defining member ormembers thereof are firmly secured to the cylinder block materialregardless of the combination of materials utilized and will not tend toICE.

Such cylinder-defining members are telescoped over suitable mandrelsdisposed in a mold chamber of a mold device whereby the rnolten cylinder block material can be subsequently disposed in the mold chamber.and's'urround the cylinder-defining members. 7

There after, either the mold deviceor the cylinder-defining members arevibrated, preferably by ultrasoniovibrating means, in such a manner thatfusion or-welding is ef-' fected between the cylinder block material andthe cylinder-defining members at the flanges of the cylinder-definingmembers, such fusion or welding not only taking place at the tips of theflanges of the cylinder-defining members but even extending into thevalleys between adjacent flanges.

In this manner, the cylinder-defining members of the resulting cylinderblock construction are metallurgically bonded to the cylinder blockmaterial and cannot readily break loose from the subsequently solidifiedcylinder block material;

Accordingly, it is an object of this inventionto provide an improvedcylinder block construction having oneor more of the novel features setforth above or hereinafter shown or described.

Another object of this invention is to provide an improved method formaking such a cylinder block construction or the like. I

A further object of this invention is to provide an improved apparatusfor making such a cylinder block construction or the like. 7

Other objects, uses, and advantages of this invention v are apparentfrom a reading of this description, which proceeds with referenceto theaccompanying drawings forming a part thereof and wherein:

break loose through continued use of the cylinder block construction.

In particular, one cylinder block construction of this inventionincludes a cylinder-defining member having a plurality of outwardlytapering flanges extending from the exterior thereof, each flangetapering to a point like tip means or both, the tips of the flanges ofthe cylinder-defining member are melted and fused with the cylinderblock material to form substantially homogeneous structures at the endsof the flanges of the cylinder-defining member. The cylinder blockmaterial is also bonded to the coating on the flanges of thecylinder-defining member from the fused tips thereof toward the bases ofthe flanges. Thus, the cylinder block materialbecomes metallurgicallybonded to the cylinder-defining member in such a manner that thecylinder-defining member cannot readily break loose from thesubsequently solidified cylinder block material.

Another cylinder'block construction of this invention is formed from oneor more or" the aforementioned cylinderdefining members except that thecylinder-defining member or members are not covered by theaforementioned coating.

FIGURE 1 is'a schematic, flow diagram illustrating one 1 method of thisinvention for forming an improvedcylinder' block construction of thisinvention.

FIGURE 2 is an enlarged, fragmentary, perspective I FIGURES 5 and 6 arefragmentary,cross-sectional views similar to FIGURE 4 and illustratevarious stages in the method of bonding the cylinder block material to ythe cylinder-defining member of this invention.

'- FIGURE 7 is an enlarged, fragmentary, cross-sectional View of thecompleted cylinder block construction of this invention and is takensubstantially on line 7-7 of the right-hand terminal view of FIGURE 1. 7

FIGURE 8 is a schematic cross-sectional view illustratingthe method andapparatus of this invention for forming another cylinder blockconstruction of this inven' tion.

FIGURE 9 is an enlarged, fragmentary, cross-sectional view illustratingthe cylinder block construction formed by the method and apparatus ofFIGURE 8.

f FIGURES 10-l2-are views similar to FIGURE 8 an illustrate otherembodiments of the method and apparatus of this invention.

members of this invention. V

While the various features of this inventionare herein after describedin connection with a' cylinder block conaisssss struction for aninternal'combustion engine or the like,

I it is to be understood that any other desired structures can besecured together by the methods and apparatus of this invention toproduce ardesired construction. Therefore, this invention is not to belimited to only the applications thereof illustrated in the drawings, asthe drawings are merely illustrative of one of the wide variety of usesof this invention.

" and disposed flush with the outer ends 34 of the main Referring now toFIGURE 1, one of the methods of i this invention for forming a cylinderblock construction or the like is schematically illustrated andcomprises the following steps.

As illustrated at station in FIGURE l, a length of cylinder-definingmember stock 11 is extruded by a conventional extruding apparatus 12.The extruded stock 11.

is subsequently cut at station 13 into a plurality of cylinder-definingmembers 14 of the desired length and ma chined to any desired degree.Thereafter, each cylinderdefining member 14 is coated at station;15 by asuitable material that bonds itself to the exterior surface of thecylinder-defining member 14 and is adapted to be bonded to the desiredcylinder block material. The thus coated cylinder-defining members 14are disposed in-asuitable cylinder block mold device 16 at station 17,the cylinderdefining members 14 being placed over suitable, heatablemandrels 18 disposed in the mold chamber 19 of the mold device 16;Thereafter, the desired 'cylinder block mate- 'rial 20 is'dispen'sedfrom suitable apparatus 21 into the mold chamber 19 of themold device 16 to be cast around the cylinder-defining members 14 and bemetallurgically bonded thereto in a manner hereinafter described. Afterthe cylinder block material 20 has solidified, the resulting cylinderblock construction 22 is removed from the mold device 16 and suitablymachined, if required, at station 23 to form the completed cylinderblock construction 22.

The cylinder-defining members '14 can be'formed from any desiredmaterial or combination of materials, and, in the embodiment illustratedin the drawings, the cylinderdefining members 14 are formedfrom'anextrudable high silicon aluminum-containing metallic materialwhich" is particularly adaptable for forming awear-resistantcylinder-defining structure for an internal combustion engine or thelike. However, the cylinderdefining members 14 can be formed'frorncopper or magnesium alloy, if-desired. As illustrated in FIGURE 2, eachextruded cylinderdefining member 14 comprises. a main cylindricalbodyportion'24 having a cylinder bore 25 passing therethrough;

A plurality of outwardly tapering, radially disposed flanges l or fins26 extend longitudinally from the exterior surface 27 of the main bodyportion 24 of the cylinder-defining member 14. -Each flange 26 has apair of opposed side 'walls 28 and 29 which converge from the base 30 ofthe respective flange '26 to the tip or outer end 31 thereof. While theopposed 'sides 28 and 29 of each flange 26 are illustrated asvconvergingtogether to form a knife-edgelike tip 31 and defining-a triangularcross-sectional configuratioruit is to be understood that the opposedsidesZS and 29 of each flange 26 can define any desiredcrosssectional'configuration whereby' the tips 31 of thefianges v paredto the cross-sectional widths of the bases 3tl'thereof,

for a purpose hereinafter described.

At the time ofcasting, these small areas are melted away; thus assuringa'metallurgical bond. The degree of metallurgical bond obtained iscontrolled by the initial 1 temperature of the finned cylinder-definingmember :14

body portion of the cylinder-defining member 14.

. When the cylinder-defining members 14 are formed from the'extrudedstock 11, the cylinder-defining members 14 can be cut fromthe stock11-and subsequently coated by a suitable bonding material 35, FIGURE 4,

at station 15, FIGURE 1, the thickness of the bonding material 35beingygreatly exaggerated in the drawings.

. Alternately, the extruded stock 11 can be coated with the bondingmaterial 35 immediately after the stock 11 has been extruded by theapparatus 12. Thereafter, the ,cylinder-defining members 14 can besubsequently cut from the coated stock 11 when needed.

As previously stated, the bonding material 35 must be of a type whichwill readily bond to the exterior surface of the cylinder-definingmember 14 and also-be adapted to be bonded to the cylinder blockmaterial 20 in a manner hereinafterdescribed. It has been found thatwhen the cylinder-defining member 14 is formed from the aforementionedaluminum-containing metallic material,

zinc, silver, molybdenum, tin, indium, or copper form suitable bondingmaterials 35 for subsequently bonding an aluminum-containing metalliccylinder block material '20, such as aluminum alloy 13, to the aluminumcylinderdefining member 14.

.When the; bonding material 35 is formed from zinc,

1 and the cylinder defining member 14 is formed from'an understood thatthe cylinder-defining members 14 can 7 be formed by a casting operation,if desired. However,

it has been found less expensive to extrude the cylinderdefining members14 than to cast the same. Therefore, the flanges 26 are designed to runlongitudinally relative to the cylinder-defining members 14 toaccommodate such extrusion operation. It is to be understood, how ever,that the flanges 26 can be disposed in any desired position around theouter peripheral surface 27 of the cylinder-defining member 14.

For example, as illustrated in FIGURE 3, the outwardly taperingflanges'26 of the cylinder-defining member 14 of this invention aredisposed circumferentially therearound and function in the same manneras the flanges 26 of the cylinder-defining member 14. Since thecylinderdefining member 14, cannot be extruded, the same can be formedby any suitable casting operation or the like.

' 26 have relatively small cross-sectionalwidths, as com- In particular,the cylinder-defining member can be die cast, permanent mold cast, orsand cast. Further, the cylinder-defining member 14' can be formed bysintering aluminum alloy particles together with or withoutWearresistantiron pellets or the like.

After the coated cylinder-defining members 14 have been provided, thesame are disposed over the mandrels 18 in the mold chamber 191 of themold device 16, the

' mandrels 18 preferably being heatable' to desired temandthetemperature of the molten aluminum, or other molten metal,'which iscast around the cylinder-defining] member 14. a

If desired, the opposed endsof the flanges 26 of each cylinder-definingmember 14 can be cut away, asat 32, to

provide a mechanical locking eifect of the cylinder-defin- A ing member14 with the cylinder block material 28 when the cylinder. block material,20 is cast over theends 33 peratures to supplement the temperature ofthe molten cylinder block material 20 in forming the subsequentmetallurgical bond between the cylinder-defining members 14 and thecylinder block material 20.

While the cylinderblock construction 22 illustrated in 7 FIGURE l isillustratedashaving four cylinderdefining members 14 provided therein,it is to be understood that the cylinder-block construction 22 couldhave one or any cylinder-defining members 14,-as de- 7 desired number ofsired.

As illustrated in'FIGURES'l and 5, the molten block material 20 'is castaround the coated cylinder-defining members 14, and the heatofthemoltencylinder block as the flanges 26 tend to heat up from thetips 31 thereof toward the bases 30, the cylinder block material becomesbonded to the coating 35 inwardly from the tips 31 toward the bases 36as schematically illustrated in FIG- URE 7.

Further, as the relatively narrow tips 31' of the flanges I 26 areheated, the same tend to melt in the manner illustrated in FIGURE 7, tofuse with the coating 35 and molten cylinder block material 20 toprovide substantially homogeneous metallic structures 36 at the freeends of the flanges 26. In this manner, the homogeneous structures 35metallurgically bond the cylinder block material 2% to thecylinder-defining member 14. Because the molten cylinder block material20 cools or solidifies at a relatively rapid rate, such melting of theflanges 26 takes place only at the tips 31 thereof. However, the

heat provided by the molten cylinder block material 20, V

with or without the heat supplied by the mandrels 18, is sufficient tocause the cylinder block material 20 to bond to the coating 35 from thefused ends 36 of the flanges 26 toward the bases 30 thereof. The extentto which the cylinder block material 20 is bonded to the coating 35 ofthe cylinder-defining members 14 throughout the length of the flanges 26depends on how long and to what temperature the flanges 26 are heated,such factors being controlled by the heatable mandrel 18 and thetempera:

ture of the poured metal.

However, it has been found that when the tips 31 of the flanges 26 ofthe cylinder-defining member 14 are fused to the cylinder-block material26 in the manner previously described to provide the metallurgicallybonded homogeneous structures 36, a suflicient amount of the coating 35on the flanges 26 is bonded to the cylinder block material .20 from thefused, ends of the flanges 26 toward the bases 30 thereof to provide agood bond between the cylinder block materialZti and thecylinder-defining members 14. V

Therefore, not only has. it been found that such metal- 7 lurgicalbonding method produces a cylinder block con other cylinder blockconstruction 4l of this invention which is illustrated in FIGURE 9, thecylinder block construction 40 comprising one or more cylinder-definingmembers 14 metallurgically bonded to the cylinder block material 20' ina manner hereinafter described.

As illustrated in FIGURE 9, the exterior surfaces of thecylinder-defining members 14 are not covered with the coating 35previously described and are fused or metallurgically secured to thecylinder block material 2%) not only at the tips 31 of the fins 2sthereof but also at the bases 30 of the fins '26 and in the vafleys 41between adjacent .fins 26 whereby the cylinder-defining members 14 willnot readily break loose from the cylinder block material 20 duringsubsequent use of the cylinder block construction 40.

The cylinder-defining members 14 and cylinder biock material 20 ofFIGURE 9-are metallurgically secured together by the method andapparatus ofFIGURE 8 in the manner nowto be described. 7

As illustrated inFIGURE 8, a suitable m'old device 42, similar to themold device 16 previously described,;has

. a mold chamber 43 adapted to receive one or'more cylinvention arecooler during operation thereof than prior 7 known constructions,because the cylinder block material of the cylinder biock constructionsof this invention readily conducts the heat away from thecylinder-defining members thereof.

While any number of flanges 26 may be provided on each cylinder-definingmember 14, it has been found that the greater the number of flanges 26provided, the greater 7 the surface area provided for such bondingoperation.

After the cylinder block construction 22 has been formed in the abovemanner, the same is removed from the molding device 16. Thereafter, thecylinder block construction 22 can be suitably machined to provide airder-defining members 14 and molten cylinder block material 20 in themanner previously described.

In particular, suitable, heatable mandrels 44, similar to the mandrels18 previously described, are secured in the proper positions in the moldchamber 43 of the mold device 42 in any suitable manner, such as beingbolted therein by bolts 45 or the like, whereby thecylinderdefining'members 14 are adapted to be respectivelytelescopically disposed over the mandrels 44 and'be properly positionedin the mold chamber 43 of the mold device 42. 7 After thecylinder-defining members 14- have been so positioned in the mold device42, molten cylinder block material 20 is poured into a mold chamber 33to surround thecylinder-defining members 14 and be metallurgically lbonded thereto by an ultrasonic welding operation.

The ultrasonic welding operation is provided by ultrasonically vibratingeither the mold device 42 or the cylinder-defining members 14 as themolten cylinder block material 20 is being poured into the mold chamber45,

whereby the cylinder block material 29 is welded or fused In thismanner, the current supplied by the alternator '48 passes through thecrystal 46 and causes the same to vibrate in the desireddirection,depending upon the particular cut of the crystal. 46, whereby thevibrations produced by the crystal 46 are transferred to the mold device42 by a suitable connecting rod 51 secured to the plate 47 at one end 52thereof and to the mold device 42 at the end 53 thereof While thecrystal 46 and alternator 4-8 can be designed in any manner well knownin the artto cause vibrations at any desired frequency, it is preferredthat the crystal 46 vibrate at a'frequency greater than 20 kilocycles soas to be beyond the audio frequency range, although lower frequencieswould work, such as 10 kilocycles or: the like.

Preferably, the rod 51 is formed from a low heat conducting materialsuch as a high nickel or chromium steel,

' interposing suitable insulatingme'ans 54 between the sup p'ortingplate 47 and the end 52 of the rod'SlL. .Alternatej '14 by the mandrels44c. 7

Therefore, it can be seen that various means havebeen provided foreither vibrating the mold device. or "the e cylinder-defining members toeffect ultrasonic welding 101' By thus Vibrating the, mold device 42 atthe ultrasonic frequencies produced by the crystal 46, it has been-foundthat the cylinder block material 20 .will be completely fused or weldedto the 'fins 2 6 of the'cylinder-defining members 14 without utilizingthe previouslyfmentioned coating 35 on the cylinder-defining,members 14,although the cylinder-defining members 14 and'cylinder block ma terial20'are formed fromdissimilar or similar aluminum alloys or thelike.

However, it is to be understood that the cylinder-defining members 14-can be covered with the coating 35 whereby the cylinder block material20 will be welded or fused to-the coating 35 inrthe above manner whenthe mold device is vibrated.

While the vibration transfer rod 51 is illustrated in FIGURES as beingattached externally to the side wall a of the molddevice 42, it is to beunderstood that the same can be attached to the mold device 42 in anydesired position, such as to the bottom Wall thereof, if desired,

'to produce the aforementioned Welding or fusion operation.

Further, the vibration transfer rod 51 can be attached a to the internalsurface of the mold device 42, if desired. a For example, the vibrationtransfer rod 51a of FIGURE is secured to the inside surface of the sidewall of the mold device 42a and is vibrated in the above manner toproduce the welding or fusing operation. In the embodiment illustratedin FIGURE 10, the vibration transfer rod 51a is formed of any suitablematerial that is able to withstand the heat of the molten cylinder blockmaterial which is poured into the mold device 42a and which will not befused or otherwise secured to the cylinder block material 20 whereby thesubsequently formed cylinder block construction can be readily removedfrom the mold V device 42a.

As previously stated, thecylinder-defining members 14 'and cylinderblock material 20 can 'be ultrasonically welded or fused together byeither vibrating the mold device 42 of FIGURE 8 or the cylinder-definingmembers 14 thereof. 7 V

One means for vibrating the'cylinder-defining members 14, rather thandirectly vibratingthe mold device 42, is illustrated in FIGURE 11wherein each mandrel 44b has a piezoelectric crystal 4eb mounted on theupper end thereof and secured thereto by suitable bolt's offasteningmeans 55 passing respectively through the mounting plates 47b and themandrels 44b. Preferably, the crystals 46b and supporting plates 4717are electrically and thermally insulated from the mandrels 44b bysuit'able insulation means 56 interposed therebetween;

In this manner, the vibrations of in FIGURE 9. a

If desired,.the vibratingmeans can be mounted directly in the mandrels44. For example, as illustrated in FIG- URElZ, the'crystals 46c andsupporting plates 470 are respectively received in suitable cavitiesrespectively provided 1n the mandrels 44c and are electrically andthermally insulated therefrom by suitable insulation means 57.

because thecylinder-defining members are metallurgically bonded to thecylinder block material and will not readily v break loose therefrom, asin the prior art.

While piezoelectric crystals have been illustrated in the drawings asprovidingfthe means for vibratingthe mold deviceor cylinder-definingmembers, it is to be u'nder- .stood thatother vibratingmeans may beutilized, as

desired. 7

It has been found that not only does the ultrasonic vibrations-causefusion or welding between the cylinderdefining members 14 and cylinderblock material 20, but

, also the ultrasonic vibrations improve the physical properties of theresulting casting by reducing the growth of 7 large crystals and retardsalloy segregation.

While it"is not illustrated, it is to be understood that the vibratoryrods interconnecting the ultrasonic transducers with the various molddevices could be cooled in any desired manner.. For example, thevibratory rods can be cooled by circulating a heat exchange mediathrough the interior of the rods.

Returning now'to the features of this inventionlconcerning the coatingof the exterior of the cylinder-defining members: 14 of FIGURE 1,.it hasbeen found that'the cylinder-defining members 14 can berzincated toprovide the coating for the above purpose.

In particular, each cylinder-defining member 14 is first caustic etchedand' rinsed. Thereafter, each cylinderdefining member 14 is deoxidizedand rinsed. The de-' oxidized and rinsed cylinder-defining member 14is'then dipped in a zincate solution:for approximately thirty secondsand then rinsed. Subsequently, the zincated cylinder-defining member 14is dipped in a nitric acid solution of approximately 50% concentrationfor approximately ten seconds.

Thereafter, the zincated cylinder-defining member 14is again dipped.into a zincate solution for approximately thirty seconds and thenrinsed to complete the zincating process.

' It has been found that the zincate solution can consist of 100 gramsof zinc oxide and 525 grams of caustic per liter of water. Optionally, asmall percentageof half ,and half Rochelle salts and ferric chloride canbe added to the zincate solution.

This-zincating process produces a superior zinc coating 35 on thecylinder-defining members 14 and can'be economically automated.

p The thus zincated cylinder-defining members 14 can be utilized in anyofthe above methods to produce the desired cylinder block constructionsor the like.

i In addition, it has been found that the cylinder-defining members 14can be formed by the method and apparatus 58 illustrated in FIGURE 13.

'In particular, a cylinder-defining member 14 is formed by casting thedesired metallic material 59 in asuitable 1 mold device 60, the molddevice 60 being so constructed and arranged that the same will producethe longitudinally disposed of circumferentially disposed fins 26 or .26on the exterior surface of. the cylinder-defining member I 14 duringthecasting operation.

Thus, thevibrations produced from thecrystals' 46; are

respectively transferred to the cylinder-defining members fusion betweenthe cylinder-defining members and the cylinder block material, wherebythe resulting cylinder block construction is a substantially unitarystructure p A mandrel 61 is disposed in thecentral portion of the molddevice 60 and cooperates therewith to define the central bore 25 passingthrough the cylinder-defining member 14.

If desired, suitable thin, disc-shaped permanent or '7 electric magnetscan be incorporated in the mandrel 61 to hold in position a properamount of iron particles 62 or the like that will subsequently linethe'interior surface of the cylinder-defining member 14 to provide awear-resistant surface. V 7

For example, the iron particles 62 can 'be disposed around the mandrel61 and will adhere thereto in the proper thickness because of theaforementioned magnets, Thereafter, themolten metallic material 59 iscast into the molddevice whereby the layer of iron-par ticles '62 arecast in the molten'metallic material 59 and form the interior surfacethereof.

' 1 wherein said coating is zinc.

The resulting cylinder-defining member 14 can be utilized in any of theabove procedures to form the desired cylinder block construction or thelike.

While there are many ways to produce the cylinderdefining members 14 byextruding the same, it is desirable to prevent the exterior surfacethereof from oxidizing before the cylinder-defining members 14 arecovered by the aforementioned coating 35.

One such method would be to surround the extruded stock 11 as it leavesthe extruding apparatus 12 of FIG- URE 1 with an inert gas shieldwhereby no oxidation of the aluminum-containing extruded stock 11 cantake place.

While the extruded stock 11 is surrounded by the inert gas shield,various metals can be sprayed'cr impinged upon the exterior surface ofthe extruded stock 11 to form the aforementioned coating 35.

Another such method is to extrude the stock 11 directly into a moltenbath of zinc or the like as it leaves the extruding apparatus so thatthe aforementioned coating 35 can be formed on the extruded stock 11before the same is exposed to the atmosphere and oxidizes.

For example, see FIGURE 14 wherein the extruding appartus 63 has theextruding end thereof forming one side of a container 64 carrying amolten bath 65 of zinc or. the like. 7

In this manner, the stock 11 is directly extruded into the molten metalbath 65 as it leaves the extruding 8. A cylinder block construction asset for in claim 1 I wherein said coating is indium.

9. A cylinder block construction as set forth in claim 1 wherein saidcylinder-defining member is one aluminum alloy and said block materialis another aluminum alloy having agreater heat conductivity than theheat conductivity of said cylinder-defining member.

10. A cylinder block construction comprising a cylin- V der-definingmember having a plurality of outwardly tapering fins extending from theexterior thereof, a coating of bonding material disposed on the exteriorsurfaces of said fins, and cylinder block material surrounding saidcylinder-defining member and being bonded to said fins by said. coatingfrom the tips'of said fins toward the bases thereof, said cylinder blockmaterial and said'tips of said fins being fused to provide substantiallyhomogeneous structures at said tips of said fins. 11. A cylinder blockconstruction comprising a cylin der-defining member having a pluralityof outwardly tapering fins extending from the exterior thereof, and

cylinder block material surrounding said cylinder-defining member andbeing bonded to said fins from the tips of apparatus 63 so as to becompletely'covered by the coat ing 35 before any oxidation of theexterior surface of the extruded stock 11 can take place If desired, theextruding'apparatus 63 can be tilted in such a manner that the extrudedstock 11 passes out of the bath- 65 so as to be subsequently cut intothe desired lengths as the stock 11, is bein continuously formed andcoated.

' Therefore, it can be seen that there has been provided 7 improvedcylinder block constructions and improved methods and apparatus formaking the same or the like,

whereby the cylinder-defining members are metallurgically bonded to'thecylinder block material and will not tend to break loose. therefromduring subsequent use of the cylinder block constructions.

While the form of the inventionnow preferred: has 1 been disclosed asrequired by the statutes, other forms may be used, all coming within thescopeof the claims bonding material disposed on the exterior surfaces ofsaid fins, and cylinder block material surrounding saidcylinder-defining member and being bonded to said fins by said coatingfrom the tips of said fins toward the bases thereof, said tipsof saidfins and, said coating and said cylinder block material in the region ofsaid tips of said cylinder defined by said member.

said fins toward thebases. thereof, said cylinder block material andsaid tips of said fins being fused to provide substantially homogeneousstructures at said tips of said fins.

' 12. A cylinder block construction as set forthin claim 11 wherein saidfins of said cylinder-defining member are disposed'substantiallycircumferentially relative to' the 13. A cylinder block constructionasset forth in claim 11 wherein said fins of said cylinder-definingmember are disposed substantially parallel to the longitudinal axis 1 ofthe cylinder, defined by .said member.

' 14. A cylinder block construction comprising alcylindef-definingmember having a plurality of outwardly j tapering fins extending fromthe exterior thereof, "and cylinder block material surrounding saidcylinder-defining .member and being fused with thetips of said fins'ltoprovide substantially homogeneous structuresat the tips of said fins..

15. A cylinder block construction comprising a cylin- 'der-definingmember of one aluminum-containing mate- .r ial, a coating. of bondingmaterial disposed on the exterior surface ofsaid cylinder definingmember, and a cylinder block of another aluminum-containing materialsurrounding said cylinder-definingmember and being bonded thereto by{said coating.

fins being fused to provide substantially homogeneous structures at saidtips of-said fins.

2 A cylinder block construction as set forth in claimi 1 wherein saidcylinder-defining member is an aluminum Y alloy.

4. A cylinder block construction as set forth in claim 3. A cylinderblock construction as set forth in claim 1 wherein said block materialis an aluminum alloy.

l wherein said coating is silver.

na in ci ed in the file or this patent UNITED. STATES PATENTS I I jSalisbur itm 1e 17, 1902 881,584 Hoifrnan Mar. 10,1908

1,528,947 7 Preston L Mar. 10, 1925 I 1,594,446 Boegehold Aug. 3, 19261,807,689 .Deputy IuneZ, 1931 1,902,350 Whitakerf Mar. 21, 19332,062,394 Brown Dec. 1,-1936' 2,327,259 Gay Aug. 17, 1943 2,433,903Hensel e Jan. 6, 1948 2,475,396 r Lester July 5-, 1949 2,511,068

Kai1 'Iune13 1950'

1. A CYLINDER BLOCK CONSTRUCTION COMPRISING A CYLINDERDEFINING MEMBERHAVING A PLURALITY OF OUTWARDLY TAPERING FINS EXTENDING FROM THEEXTERIOR THEREOF, A COATING OF BONDING MATERIAL DISPOSED ON THE EXTERIORSURFACES OF SAID FINS, AND CYLINDER BLOCK MATERIAL SURROUNDING SAIDCYLINDER-DEFINING MEMBER AND BEING BONDED TO SAID FINS BY SAID COATINGFROM THE TIPS OF SAID FINS TOWARD THE BASES THEROF, SAID TIPS OF SAIDFINS AND SAID COATING AND SAID CYLINDER BLOCK MATERIAL IN THE REGION OFSAID TIPS OF SAID FINS BEING FUSED TO PROVIDE SUBSTANTIALLY HOMOGENEOUSSTRUCTURES AT SAID TIPS OF SAID FINS.